BMW 420I MOT Pass Rate & Official DVSA Failure Statistics

BMW 420I MOT History and Failure Rates vs UK National Average

The BMW 420I passed on its first attempt in 90.1%, and its overall record sits +10.0 percentage points above the national average for all cars. These figures come from every recorded DVSA MOT test for the BMW 420I in the 2023–2025 data: 11,348 tests across 4 model years (2020–2023). A test still carries exactly one pass or fail verdict.

Figures are computed from every recorded DVSA test for this model in the 2023–2025 data.

Most Common BMW 420I MOT Problems by Failure Category

Every MOT failure a tester records belongs to one inspection section of the DVSA manual. For the BMW 420I, the Tyres section leads the record — the breakdown below shows where the recorded failures cluster, then the exact strings behind the three biggest sections.

Shares are over the BMW 420I's recorded defect strings, merged across its year pages.

Top Recorded BMW 420I DVSA MOT Test Statistics & Defect Descriptions

The descriptions below are the exact DVSA failure strings testers recorded most often for the BMW 420I, each with how many of the model's 11,348 tests it was noted on.

• "Has a cut in excess of the requirements deep enough to reach the ply or cords" (Major) — noted on about 253 BMW 420I tests, 2.2% of the model's MOT record.
• "Has a bulge, caused by separation or partial failure of its structure" (Major) — noted on about 252 BMW 420I tests, 2.2% of the model's MOT record.
• "Tread depth below requirements of 1.6mm" (Major) — noted on about 154 BMW 420I tests, 1.4% of the model's MOT record.
• "Has ply or cords exposed" (Major) — noted on about 129 BMW 420I tests, 1.1% of the model's MOT record.
• "Windscreen damaged but not adversely affecting driver's view" (Minor) — noted on about 120 BMW 420I tests, 1.1% of the model's MOT record.
• "Headlamp aim too high" (Rectified) — noted on about 72 BMW 420I tests, 0.6% of the model's MOT record.

Best and Worst BMW 420I Model Years by Pass Rate

The strongest BMW 420I model year on record is 2023 (93.6% across 173 tests), and the weakest is 2021 (90.7%). The gap between them is 2.9 points. Years with fewer than 50 recorded tests are excluded, so these are the years with enough MOT history to mean something.

Newest model year first. Only years with at least 50 recorded tests are listed.

Pre-MOT Inspection Checklist for BMW 420I Owners

These checks follow this BMW 420I's own most-recorded failure strings, starting with what a tester is most likely to flag on a BMW 420I.

• the tyre tread — “tread depth below requirements of 1.6mm”

  Check all four tyres cold, including the inner shoulder where wear hides — 1.6mm across the central three-quarters is the legal limit, and most testers fail at 1.6mm without argument.

• the windscreen — “windscreen damaged”

  Check the driver’s side of the screen within the swept area for chips and cracks; anything larger than 10mm in the driver’s central view is a fail. Most chips can be resin-repaired for far less than a new screen.

• the lights — “headlamp aim too high”

  Switch everything on and walk round the car: both headlamps on dip and main, every indicator, both brake lights, reverse, fog and the two number-plate lamps. A bulb is a few pounds and a five-minute job.

Derived from the DVSA failure strings testers recorded for the BMW 420I. A check that finds nothing means the item is likely fine, not that the test is guaranteed.

Where the BMW 420I is most common

Across every 420I model year on record (2020–2023): 8,167 BMW 420I cars tested in a recordable postcode area, across 11,346 tests. Birmingham (B) has the most, with 304 cars tested there. Cars are counted by the postcode area of the MOT station, so this is where they were tested, not necessarily where their owners live.

The twenty areas with the most BMW 420I cars in the record, sorted by car count — sort the columns for a different question. Cars tested at a station whose postcode area could not be resolved are counted in the model's total but in no area, so the shares add up to slightly under 100% even across every area, and an area's cars are a subset of the model's. Pass rate is blank below 30 tests in an area, where a percentage is noise rather than a finding. How this model's pass rate varies by postcode →

Frequently Asked Questions: BMW 420I MOT & Reliability